S
M
T
W
T
F
S
30
85°
62°
31
81°
54°
1
65°
49°
2
66°
50°
3
63°
55°
4
64°
52°
5
70°
54°
6
72°
55°
7
79°
59°
8
86°
64°
9
95°
71°
10
96°
68°
11
89°
60°
12
77°
54°
13
80°
58°
14
86°
53°
15
85°
50°
16
80°
54°
17
82°
55°
18
83°
54°
19
85°
55°
20
82°
54°
21
84°
53°
22
84°
48°
23
81°
50°
24
84°
49°
25
77°
46°
26
81°
52°
27
77°
48°
28
77°
45°
29
80°
48°
30
84°
51°
1
85°
51°
2
85°
50°
3
84°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Challenge-Brownsville
Challenge-Brownsville's September 2026 forecast shows daily high temperatures ranging from 77° to 96°, with overnight lows between 45° and 71°. The average high for September is 83° with an average low of 53°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Challenge-Brownsville. See also: October | November | December.
